import React, { Component } from "react";

export default class Demo extends Component {
    state = { count: 0 };

    add = () => {
        // 对象式的 setState
        // // 1.获取原来的 count 值
        // const { count } = this.state;
        // // 2.更新状态
        // this.setState({ count: count + 1 }, () => {
        //     console.log(this.state.count);
        // });

        // 函数式的 setState
        this.setState((state) => ({ count: state.count + 1 }));
    };

    render() {
        return (
            <div>
                <h1>当前求和为：{this.state.count}</h1>
                <button onClick={this.add}>点我+1</button>
            </div>
        );
    }
}
